It is well known for water and air craft the primary limitation on speed is drag: terminal velocity is reached when the thrust force is matched by the drag force. It is also well known that the ambient pressure of fluids at sea level is about one hundred thousand Newton per square meter. Fractional imbalances in this pressure on an object can result in very high thrust forces and accelerations. It is conceivable that a craft could attain very high speed and acceleration under conditions of reduced frontal drag and reduced frontal ambient pressure.
It is well known that, according to the kinetic theory of gases, the pressure p exerted by the gas molecules on a stationary wall is proportional to the square of the root mean square velocity Vrms of the molecules. The pressure p is given byp=(dVrms2)/3where d is the density of the ideal gas. If the gas is brought to a thermodynamic state where it undergoes a phase change to a liquid or solid state then most of the molecules attract together. The density of the gas reduces and there is a corresponding pressure drop or implosion. The heat of condensation opposes the phase change and pressure drop, and a coolant or heat sink must absorb the heat if the phase change is to continue.
If a gas undergoes condensation on contact with a cooler surface then the partial pressure exerted by the condensing gas molecules is half of the pressure that would have been exerted on the surface if the molecules had elastically rebounded. As a result of the reduced pressure, if a cloud of vapor remains in contact with the cool surface, it moves towards the cool surface and condenses on it. Also the cool surface will move towards the cloud of vapor if free to do so. This dynamical behaviour can be maintained as long as the surface remains cool and the stream of condensing vapor is replenished.
Brown's gas is a stoichiometric mixture of hydrogen and oxygen allowing complete combustion to form pure steam. It can be produced by electrolysis of water. It is dangerous to store in larger quantities due to its highly explosive nature. If a cool heat sink is provided in contact with the explosion there can be a subsequent rapid implosion as a result of condensation of the steam.
Various systems are known for propelling craft, including motor-driven propellers, and jet propulsion units which produce thrust by discharge of a stream of fluid.
U.S. Pat. No. 3,402,555 (Piper) discloses a steam jet nozzle system for propelling watercraft. In the nozzle system, steam is generated and discharged under high pressure to provide propulsion. The nozzle system includes a nozzle having an entrance end and an exit end. Steam enters the nozzle through the entrance end. Raw water from the body of water through which the watercraft is to be propelled is introduced into the nozzle so as to be converted into steam to supplement the steam already in the nozzle. The propulsion is not provided by a jet stream of water but rather by generation and discharge of steam under high pressure.
U.S. Pat. No. 6,662,549 (Burns) discloses a propulsion system for generating a fluid stream utilising a driving fluid without relying solely on momentum transfer. Burns discloses a propulsion system comprising a flow passage having an intake, for communicating with a source of working fluid, and outlet. A mixing zone is disposed within the flow passage between the intake and the outlet. There is a means for introducing a hot compressible driving fluid into the mixing zone, whereby interaction between the driving fluid and the working fluid in the mixing zone develops a pressure reduction in the mixing zone to cause working fluid to be drawn from said source into the mixing zone and propelled towards the outlet. And there is a means for aerating the working fluid with an aerating gas prior to interaction of the driving fluid in the mixing zone whereby a three-phase fluid regime is created in the mixing zone by virtue of the interaction of the aerating gas, the working fluid and the driving fluid.
The interaction between the hot compressible driving fluid and the working fluid involves contact of driving fluid with the working fluid causing rapid cooling of the driving fluid to produce the pressure reduction in the mixing chamber. The rapid pressure reduction is in effect an implosion within the mixing zone. The feature of the driving fluid being compressible allows for a volumetric change upon rapid cooling of the driving fluid.
The interaction between the hot compressible driving fluid and the working fluid preferably also involves momentum transfer from the driving fluid to the working fluid.
Steam is a particularly suitable driving fluid, as it can be generated readily and efficiently. Furthermore, steam can be expanded easily and is capable of rapid volume reduction upon condensation to generate the necessary implosion effect.
During operation of the propulsion system, the driving fluid may be projected or injected into the working fluid on a continual basis or on an intermittent basis such as in a pulsed fashion.
The aerating gas may comprise air or any other appropriate gas or gaseous mixture. Aeration of the working fluid produces a two-phase mixture which has some compressibility. It is believed that the aeration has the effect of lowering the density of the two-phase mixture in comparison to the working fluid, so assisting in the transfer of the working fluid along the flow passage towards the mixing chamber. The lower density of the two-phase mixture is also advantageous as the density is closer to the density of the driving fluid, so assisting momentum transfer. Momentum transfer is increased as the density of the two phase mixture approaches the density of the driving fluid.
U.S. Pat. No. 3,259,065 (Ross et al.) discloses a means for minimizing the drag and temperature rise at the nose or leading edge portions of supersonic vehicles. A virtual nose cone is provided by one or more jets of high velocity gas, protected ahead of the vehicle either on-axis or at a slight angle thereto depending on the particular angle of attack. The gas is expelled from a nozzle at supersonic velocity to form a jet or virtual spike.
This gas is expelled forward into the oncoming supersonic air stream until it terminates where a shock wave commences. Behind the shock wave, a conical subsonic boundary layer of trapped air and gas forms. The air flow around the vehicle is substantially identical to that which would have been produced by the conventional elongated nose cone. While the forward portion of this virtual spike does experience heating, no structural problem is introduced since the trapped air and gas is continually replaced.
In currently unpublished US patent application(s) and published articles Robert Daniel Hunt (Hunt Aviation, www.fuellessflight.com) discloses gliding airships and underwater craft involving cyclical buoyancy change for gliding up and down. This revolutionary invention can extract renewable thermal and gravitational potential energy from the atmosphere or water. In some embodiments of the airships the buoyancy control is at least partly dependent on exchange of heat with the ambient atmosphere. In particular, a phase change fluid or refrigerant can be heated and cooled through its boiling point to provide buoyancy control. For the purposes of the present invention such a cyclically gliding craft will be called a cyclider.
It is noted that the energy required for buoyancy control is partially independent of the gravitational potential energy released by the rise and fall of such a craft. In fact under certain conditions the energy released can far exceed the energy required and fuel-free flight powered by the renewable energy of the atmosphere can occur.
The present invention seeks to provide a motion generating system generating motion utilizing a pressure reduction resulting from heat transfer from a hot fluid introduced near an external surface of an object.